The origin of the modern keyboard as the primary method for inputting text and data from a human to a machine dates back to early typewriters in the 19th century. As computers were developed, it was a natural evolution to adapt the typewriter keyboard to be used as the primary method for inputting text and data. While the implementation of the keys on a typewriter and, subsequently, computer keyboards have evolved from mechanical to electrical and finally to electronic, the size, placement, and mechanical nature of the keys themselves have remained largely unchanged.
As computers evolved and graphical user interfaces developed, the mouse pointer became a common user input device. With the introduction of portable “laptop” computers, various new pointing devices were invented as an alternative to the mouse, such as trackballs, joysticks, and touchpads (also referred to “trackpads”). The overwhelming majority of laptop computers now incorporate the touchpad as the primary pointing device.
Prior to computers, a common office instrument used for performing numerical calculations was the “adding machine.” This device incorporated number keys along with common mathematical operation keys, such as add, subtract, multiply, and divide. The operator performed data entry using these machines, which then displayed the result, printed the result, or both. Experienced adding machine operators were able to memorize the location of the keys and enter data and perform operations very quickly without looking. As computers became common, the need for efficient numeric entry persisted and the “adding machine” functions were added to computer keyboards in the form of a numeric keyboard (or “numpad”) typically located to the right of the standard keyboard.
Combining the three primary user interface devices of keyboard, touchpad, and numpad into a single device results in the device becoming unreasonably large. The problem is further complicated by the fact that many modern keyboards incorporate yet additional keys for page navigation, multimedia controls, gaming, and keyboard settings functions. The result can be a “keyboard” that is often larger than the computer itself.
Further, a new form of portable computing device has recently emerged, commonly referred to as a “tablet” computer. This type of portable computing device typically does not have an integrated keyboard, relying instead solely on touch as the primary means of human-computer interface. Many believe tablets and, eventually, “touch surfaces” that are integrated into daily life will become the standard way humans will interface with “computers” in the future.
While this new paradigm of touch-centric computing has many advantages, one marked disadvantage is the lack of a keyboard. Although external physical keyboards can typically be connected to touch-screen computers, it often defeats the purpose of the device and negates its advantages over traditional laptop computers.
As the evolution of computing devices has progressed toward touch-based user interfaces, a natural evolution for the idea of a keyboard has been to carry it into the virtual world of the computer display by designing onscreen keyboards. Smaller touchscreen devices such as PDAs and Smartphones don't have sufficient screen size to allow people to type on an onscreen keyboard using the conventional method of touch-typing with multiple fingers. As a result, a plethora of inventions have sought to provide alternative text input methods that require less physical space than a conventional keyboard layout. While these inventions have varying benefits for entering text on a small onscreen keyboard, they don't allow text entry at speeds that compare to standard “ten-finger” typing on a conventional keyboard.
Thus, it is desirable to find a yet faster way for entering text that more closely matches the typing style learned on conventional keyboards. In doing so, there are three primary challenges: first, overcoming the relatively large amount of display real estate required for a 10-finger onscreen keyboard. Second, overcoming the lack of tactile feedback common in mechanical keyboards. And third, allowing the user to rest their fingers on the “home-row” position on the onscreen keyboard, as they normally would on a conventional electromechanical keyboard.
Traditionally, these touch sensitive surfaces respond immediately to the user's touch (or release). The paradigm is simple: point, touch, select. While this works well for many applications, it is problematic in situations where the user desires to rest their hands and/or fingers on the surface. A touch-sensitive keyboard (onscreen or stand-alone) is a good example of such a situation; a trained ten-finger touch typist relies on resting their fingers on the home row of the keyboard and then pressing keys to initiate an action. On traditional touch-sensitive surfaces, this isn't possible because as soon as the user touches the surface to rest their fingers, an action is initiated. These solutions don't take into account the need for the user to rest their hands/fingers on the surface.